Databases, Systems & Networks

Introduction

Full-text search, or FTS, is a technique used by search engines to find results in a database. You can use it to power search results on websites like shops, search engines, newspapers, and more.

More specifically, FTS retrieves documents that don’t perfectly match the search criteria. Documents are database entities containing textual data. This means that when a user searches for « cats and dogs », for example, an application backed by FTS is able to return results which contain the words separately (just « cats » or « dogs »), contain the words in a different order (« dogs and cats »), or contain variants of the words (« cat » or « dog »). This gives applications an advantage in guessing what the user means and returning more relevant results faster.

Technically speaking, database management systems (DBMS) like MySQL usually allow partial text lookups using LIKE clauses. However, these requests tend to underperform on large datasets. They’re also limited to matching the user’s input exactly, which means a query might produce no results even if there are documents with relevant information.

Using FTS, you can build a more powerful text search engine without introducing extra dependencies on more advanced tools. In this tutorial, you will use MySQL 5.6 to query a database using full-text search, then quantify the results by their relevance to the search input and display only the best matches.

Prerequisites

Before you begin this tutorial, you will need:

• One Ubuntu 16.04 server set up by following this Initial Server Setup with Ubuntu 16.04 guide, including a sudo non-root user and a firewall.
• MySQL 5.6 or higher installed by following the How To Install MySQL on Ubuntu 16.04 guide.

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Introduction

While many users need the functionality of a database management system like MySQL, they may not feel comfortable interacting with the system solely from the MySQL prompt.

phpMyAdmin was created so that users can interact with MySQL through a web interface. In this guide, we’ll discuss how to install and secure phpMyAdmin so that you can safely use it to manage your databases from an Ubuntu 16.04 system. 

Prerequisites

Before you get started with this guide, you need to have some basic steps completed.

First, we’ll assume that you are using a non-root user with sudo privileges, as described in steps 1-4 in the initial server setup of Ubuntu 16.04.

We’re also going to assume that you’ve completed a LAMP (Linux, Apache, MySQL, and PHP) installation on your Ubuntu 16.04 server. If this is not completed yet, you can follow this guide on installing a LAMP stack on Ubuntu 16.04.

Finally, there are important security considerations when using software like phpMyAdmin, since it:

• Communicates directly with your MySQL installation
• Handles authentication using MySQL credentials
• Executes and returns results for arbitrary SQL queries

For these reasons, and because it is a widely-deployed PHP application which is frequently targeted for attack, you should never run phpMyAdmin on remote systems over a plain HTTP connection. If you do not have an existing domain configured with an SSL/TLS certificate, you can follow this guide on securing Apache with Let’s Encrypt on Ubuntu 16.04.

Once you are finished with these steps, you’re ready to get started with this guide.

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